/*
   A C-program for MT19937, with initialization improved 2002/1/26.
   Coded by Takuji Nishimura and Makoto Matsumoto.

   Before using, initialize the state by using init_genrand(seed)  
   or init_by_array(init_key, key_length).

   Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
   All rights reserved.                          

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

     1. Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.

     2. Redistributions in binary form must reproduce the above copyright
        notice, this list of conditions and the following disclaimer in the
        documentation and/or other materials provided with the distribution.

     3. The names of its contributors may not be used to endorse or promote 
        products derived from this software without specific prior written 
        permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


   Any feedback is very welcome.
   http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html
   email: m-mat @ math.sci.hiroshima-u.ac.jp (remove space)
*/

#ifndef __OG_RANDOM_H__
#define __OG_RANDOM_H__

namespace og {
	/*
	==============================================================================

	  Random

	==============================================================================
	*/
	class Random {
	public:
		Random() { storedSeed = 0; mti=N+1; };
		Random( uLong seed );

		void				SetSeed( uLong seed = 0 );
		void				SeedTime( void );					// Sets the seed at ostime of calling function
		uLong				GetSeed( void ) const;

		//! @todo	what about negative ones ?
		uLong				RandomULong( void );				// random uLong in the range [0,0xffffffff]
		int					RandomInt( void );					// random integer in the range [0,0xffffffff]
		int					RandomInt( int min, int max );		// random integer in the range [min, max]
		bool				RandomBool( void );					// random boolean value [false, true]
		float				RandomFloat( void );				// random number in the range [0.0f, 1.0f]
		float				RandomFloat( float min, float max );// random number in the range [0.0f, 1.0f]
		float				SymmetricRandom( void );			// random number in the range [-1.0f, 1.0f]

	private:
		// Period parameters
		static const int N = 624;
		static const int M = 397;
		static const uLong MATRIX_A = 0x9908b0dfUL;		// constant vector a
		static const uLong UPPER_MASK = 0x80000000UL;	// most significant w-r bits
		static const uLong LOWER_MASK = 0x7fffffffUL;	// least significant r bits

		uLong	mt[N];	// the array for the state vector
		int		mti;	// mti==N+1 means mt[N] is not initialized
		uLong	storedSeed;
	};
}

#endif
